Undertale: Melt
by madface7
Summary: (I admit this is sort of copying off of sixbones :P)Alphys infuses Papyrus with DT and determination starts an infection. Monsters start killing the infected and gain LOVE and grow to have the desire to kill, and Frisk, Flowey, Alphys, and Sans need to find a cure before either the infected get monsterkind or monsterkind kills each other...
1. Melt

1: Melt

Determination doesn't go well with skeletons.

You see, skeletons can't really die. They're already dead.

So how can determination revive something that's dead?

There are other reasons not to inject determination into a skeleton.

Skeletons don't have immune systems, so their magic stays in constant vigilance and tries to fight off diseases or anything foreign to their body.

Their magic doesn't do very well.

When determination goes into the body of the host skeleton, the magic tries to destroy the determination cells.

And the determination fights back.

Determination's way of fighting magic is to wriggle itself into a magic cell and take over the nucleus of the cell, controlling it.

And skeletons don't have brains, so the skeleton runs on magic to think and act.

Thus, the skeleton practically becomes determination.

Then the determination sees everything as a threat. The main threat to them is monsterkind.

Then determination cells leak out and multiply (outside of the body, of course, because they know they could kill the host by melting them) and try to make their way into another monster's body.

Then the melting starts. The skeleton melts into a big leaking version of itself. And if the magic cells hadn't been controlled by the determination, the skeleton still wouldn't be able to think.

Then the process starts again in another monster. The determination sees the brain of the monster as a threat and takes it over. Then it becomes an outbreak. Melted monsters everywhere. And nobody knows a cure... Then monsterkind all melts together into a giant made out of determination-infused monsters...

If only Dr. Alphys and Sans had known that.

Sans bursted into the lab, holding an injured Papyrus in his hands. Papyrus had a deep crack in his skull and his eyesockets were closed. "alphys, no time to explain, but papyrus is dying! do something! remember how you're going to revive those monsters? do that to papyrus! please, he's going to die!" Sans yelled.

Alphys responded, "But i-it's not ready yet! The serum hasn't been fi-"

"i don't care! just help papyrus!" Tears were welling in Sans' eyes. It looked like Sans would frown for the first time in years until Alphys brought Papyrus into the lab. Alphys gathered the determination samples and said quietly to herself, _"Please work, please work, pleease work..."_

She pushed the plunger on the syringe and gave Papyrus the determination.

Unexpectedly, Papyrus opened his eyes.

"Brother, I'm alive! I feel strange, though," Papyrus exclaimed.

Sans was estatic. He brought Papyrus home and they ate Papyrus' favorite treat, dinosaur egg oatmeal, and went to bed. Little did Sans know that Papyrus was being controlled by determination all throughout his sleep...


	2. Spread

2\. Spread

Sans awoke the next morning at one o'clock PM. He took off his pajamas and put on his hoodie, shorts, and undershirt. He teleported out of his room. "papyrus," he asked, "are you here?" Papyrus was nowhere to be found. Maybe, Sans thought, he was recalibrating his puzzles. So Sans teleported around Snowdin. He wasn't there, either. Then Sans teleported to Undynes' to see if his brother was training there.

"Sans, what's up?" Undyne asked as she opened the door for him.

"it's pap. i can't find him anywhere. he's not in snowdin or in here. i doubt he's in his bedroom. he's ALWAYS up at this time," Sans responded.

"Well, the human is visiting me right now, and after this I have to train. I can't help you at this moment," Undyne said.

"Maybe I could help," sounded a shrill voice from the inside of Undyne's fish house. Frisk's head popped out from behind the door. "I can look for Papyrus with you." So Frisk joined Sans on the hunt for Papyrus. Sans would check the obvious spots, and Frisk would peek in every nook and cranny to see if Papyrus was there.

They never found him.

Sans and Frisk had give up entirely. The only place left to look was in Papyrus' bedroom, and Frisk went to check there.

"AAAAAAAAAAAAAAAAAAAAAAAAAAAH!" Frisk screamed as they bolted out the door. "Papyrus! He's-"

"Nyeh-heeehhhh..." A white, dripping figure crawled out from the bedroom slowly. The figure resembled Papyrus. "Nyehhhhhhhhh... Sannnnssss..." Papyrus said in an eerie tone. "Iamm... determin...ed...heh...NYEH!"

"Don't get close to him, he'll melt on you!" Frisk shouted at Sans.

"how do you know he's so dangerous?" Sans asked.

"Let's just say I've been in Alphys' lab."

Then it hit Sans. The melting, the syringe... It was his fault that Papyrus was like this. It was his fault. He had created a monster. And he needed to stop it. "frisk, come on. we're going to alphys' lab." And with a crack, Sans and Frisk teleported away to the lab.

"Oh, my g-god," Alphys stuttered as Sans and Frisk walked through the door. "Are y-you coming here to talk about P-Papyrus?"

"yes," Sans said, "he's melting because of your determination serum! what do we do?"

"U-um..." Alphys stuttered, tears welling in her eyes. "I d-dont know. _Oh my god, oh my god, oh my god, i've made a huge mistake..."_  
"LISTEN." Sans said, his laid-back tone falling away to a more serious voice. "We are going to fix Papyrus even if it takes a million years." Sans said, and marched up to Alphys and accidentally stepped on the remote for the TV.

"Welcome to MTT News, beauties!" said a cheery Mettaton through the television. "Today we're going to interview some people on their opinions... on ME!" Sans was about to turn off the television when he noticed that Mettaton was in Snowdin. "Hello, beautiful, what's your name?" Mettaton asked a townsfolk rabbit

"My name i-"

Then Papyrus jumped onto the screen. The news camera fell over and the last sight of the news channel was three melting figures- all three saying in unison, "threats... all.. threats..."

Sans and Alphys glanced at each other. They both knew that the worst was coming, and they had to prepare for it.


	3. LOVE

"What?"

Alphys stared at the monitor. "I though only Papyrus was melting- why did those two start?"

Sans stared at Alphys angrily. "I should have remembered this. We used to be lab partners, remember? I tried to flush everything about this out of my head after I found out you'd messed everything up, when I helped you. I didn't remember the DT experiments. I didn't remember what G told me."

"W-Who's G?" asked Alphys, looking like she would faint of embarassment at any second.

"The first Royal Scientist. Wingding Aster." Sans rubbed his temples. Just _thinking_ about Gaster made him feel like he'd split into a million pieces. "Gaster once told me that skeletons can spread determination- just like a virus. It's my fault we're in this mess."

"N-no, Sans, I-"

"We have to find a cure, then." Frisk walked up to Sans and Alphys. "You two are the smartest people I know! Why can't you just stop worrying and try to solve this problem?" Alphys looked at Sans. She shot a look at him that meant, _She's right, you know..._ So Sans and Alphys got to work.

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Meanwhile, in Snowdin, a devious flower sprouted up next to Papyrus' house. Flowey looked around to see if his 'friend' was out to talk to him. This time, for sure, he had to be outside. This was the time Papyrus would be out training. "Oh, Papy..." said the flower. There was no reply. There wasn't even a sound. Everyone in Snowdin was gone. How had he not noticed? The usual cheerful vibe became suddenly distorted as Flowey looked around Snowdin. Why was everyone gone? Where was everyone? Flowey's thoughts were interrupted as he heard a sound- the sound of a gun firing. Flowey looked in the alley behind Papyrus' house. There sat a melting monster-it looked like one of those Ice Cap guys- next to a rabbit. The rabbit shot down the creature and pivoted.

"Stay back!" yelled the rabbit. "I'm not afraid to murder you, dumb flower!"

"You IDIOT! _I'm_ the murderer around here! What's you against a flower with demonic powers?" asked Flowey.

"A flower. Aww, isn't that cute. If you think you're strong, then fight me!"

*Murder Rabbit has engaged battle!

*Flowey: Act: Check

*Murder Rabbit 10 ATK 50 DEF

He's got some LOVE, all right. Those are some huge stats for a non-battle monster!

*Flowey: Fight: Murder Rabbit

*20 damage dealt.

Machine guns started to shoot Flowey. Instead of bullets, rabbits shot out of the guns. Flowey took 10/20 damage.

*Murder Rabbit starts frothing at the mouth.

*Flowey: Fight: Murder Rabbit

The friendliness pellets hit twice, causing Murder Rabbit to collapse.

*YOU WON!  
*You recieved 30 gold. XP at maximum, none earned.

"What the crap was wrong with that guy?" Flowey tiredly ate a friendliness pellet and healed 20 HP. He looked around, and more melting creatures were crowding around him. It seemed while he was in the Fight he hadn't noticed what was happening around him. Afraid, Flowey sprouted to as far as he could. Coincidentally, Flowey came to a spot right in the middle of where Alphys and Sans were sitting.

Sans was startled by Flowey. "Flowey, I thought I told you to stop bugging us. Go away."

"But Smiley Trashbag-"

"Don't call me that, petalface."

"Fine, but Sans, I'm here to escape these weird monster. there was this non-battle monster who actually got in a FIGHT wth me. He had almost 12 LOVE! No one was in Snowdin but him and this melting monster. I eventually killed him, though, so ha-ha, dumb monster. Then a bunch more melting monsters crowdwd around me, so I fled. Dang! Why didn't I just kill them?"  
"Flowey, so you're telling us you got in a battle with a non-battle monster with a lot of execution points? But then-" Sans' expression changed from confused to sad. "He might have murdered Papyrus."


	4. Hands

No.

Sans wouldn't accept it. He couldn't.

Papyrus could have died. He was stuck with a sociopath in a deep, dank lab. To top it all off, it was the apocalypse. How could the day get any worse?

Sans stopped focusing on his problems and got to work. _Let's see… The Rules of DT, chapter 12… the extraction of DT to a liquid from a melting monster would cause death, because the monster is technically dead… no, we can't use that… How are we ever supposed to find a cure?_

"S-Sans?" Alphys asked. Have you figured out anything? You seem… focused." Sans looked like he was in a trance- his eyes were blank while reading his book; he seemed as tired as an old, worn out shoe.

"%&*% #))$ #^ $*-%(##! *%#&$ # &%^, &!" Sans stammered.

"W-What?" Alphys asked.

"Alphys, I said, 'This book is useless! Thanks a lot, G!' Didn't you hear me? Are you deaf?"

"B-but you just spoke gibberish…"

"I don't know what you're talking about."

The next day, as Sans was working, Flowey sprouted up near him. "Sans, what the heck! Aren't you supposed to be working on fixing up _those_ guys? Why did you doodle all over this piece of paper? Wait- are those SMILEY FACES? Are you out of your MIND?"

"What? You can't read this?"  
"Read? These are drawings!"

"Read it again, sociopath. You're crazier than I thought."

The next day, Frisk noticed that Sans was covering up his eye and grasping his hands. "Are you okay, Sans? You look hurt."

"No, no, it's fine." Sans' eyes flashed and Frisk was startled.

"Are you sure? Your eyes... they're glowing."

"What? No, they're not…"

Suddenly, the door burst open. Alphys ran into the room. "W-we're being ambushed by DT monsters! There's nowhere left to run- we're trapped! What do we do, what do we do…"

Frisk had a bright idea. "I know. Deactivate the power. The elevator will switch off. We can bunker down here where it's safe."

Flowey, on the other hand, was less optimistic. "But what if they melt into here? They're pretty much liquid. We're gonna die anyways."

"I'd say it's worth a shot," said Sans. "Let's do it."

Alphys switched off the power to the True Lab (it never really used power anyway) and they heard sloshing…

The melting behemoths had left. There was no sound at all. To be safe, they waited ten minutes before turning the power back on.

Three full weeks of hard labor later, they finally found a cure. Or… half of one. Sans found out how to negate the effects of DT for a short time, but it was only a small revelation.

Sans had been in a terrible mood for months. He crawled into bed, and had a dream. In his dream, he crept through lab very slowly. When he got into the mirror room, he glanced. He was Gaster. The next mirror was worse. He saw himself.

Melting.

His dream ended with symbols and hands, but he knew what they meant.

"I am trying to show you something. Be warned. The end is near. Two creatures and three monsters will remain. You are going to die.

"She will return."


	5. Mishap

5\. Mishap

(INITIATING ULTIMATE CREEPY INTRO!)

The lab was as dark as night.

Because it, um, was, night, and the lights were off

CUT! That intro was terrible

(Take 2)

The lab was as dark as night. Sans was drifting off to sleep, in a bed beside Alphys.

Flowey was hungry. He hadn't eaten since the day before. He wanted to get a snack, but he was too short to reach the fridge or popato chisp dispenser. Plus, he didn't even have arms. So Frisk had to do everything for him. It annoyed Flowey, but being a flower had its upsides, like being able to pelt people with bullets for fun.

"Frisk? Where are you? Come out here!"

"In the kitchen. I'm grabbing a midnight snack. It's odd to stay up this late; Mom made me go to bed at 6:00 PM every night. Until... she turned into one of _those._ Actually, who knows? Maybe she's safe. Flowey, do you miss her? At least a little?"

"I only miss someone I mistook you for. Even then, Asriel misses her more than me. I couldn't give a crap about Toriel. I've killed her more times than I'll ever kill you."

Frisk nodded sadly. She had tried a _ton_ over the past month to make Flowey feel at least a _little_ compassion, obviously failing. Then, she heard a low groan.

"What was that?" Frisk screamed.

"I dunno," said Flowey. Then Frisk heard it.

"BEAT IT, SCRUBS! GET AWAY FROM ME, DUMB MELTING THING, OR I'LL TEAR APART EVERY BONE IN YOUR BODY!"

More DT monsters, and a LOVE monster.

No matter how harsh the voice was, it soothed Frisk. Like it was familiar. The words didn't matter, it was the voice. She felt... safe.

Toriel.

Frisk ran into the elevator and bolted out the door. Flowey sprouted up behind her. "Frisk! Are you an idiot? Why are you running into here? Remember, Toriel's a psychopath now!"

"Well, well, look what we have here." Toriel turned around and smirked at the two. "Two people who have just _wandered_ into my clutches." She licked her lips.

*Toriel engages battle.

*Frisk: Act: Check

*ATK 900 DEF 900

Frisk was swarmed by fire. She took 19 damage.

Flowey took 3 damage and fled.

Frisk wasn't dismayed that Toriel was attacking her. Frisk would just reach in her soul and SAVE her, no big deal.

*Frisk: Act: SAVE

(HAH, U THOUGHT IT WOULDN'T WORK? IT REALLY WAS THAT EASY. JUST LIKE IN UNDERTALE.)

"M-my child... I am sorry I have hurt you. I don't know why I attacked those things, but I am glad you are all right."

*Toriel took 9999999999999999999999999999999999999 damage.

*Toriel took -9999999999999999999999999999999999999 damage.

YOU WON! You recieved 0 XP and 20 gold.

Frisk didn't notice, but during the end of the FIGHT, a monster had come in. It was a tall, melting monster.

And it infected Toriel.

Frisk screamed. Flowey sprouted up to see what was going on. The melting monster grabbed Frisk by the neck and breathed very heavily in her face. While that was happening, Frisk had a sensation of power.

Determination doesn't go well with red souls.

You see, too much determination can create a second substance.

This substance is as some people like to call hate.


	6. Return

Chara opened up her eyes. She couldn't make out much because her head was fuzzy, eyes blurred, but she felt a cold hand dragging her across the room. She saw a little yellow thing close to her- what was it? She finally came to her senses and found she was being dragged across Alphys' lab.

The thing dragging her across the room went exceedigly slowly, so she tried to stab it- but it somehow dodged. It hissed at her and ran away.

She looked at the yellow thing and realized that it was Flowey. He looked beat up- he had a scar on his face and one of his petals was torn. He looked shocked- but Chara couldn't find out why. Finally, the flower spoke. "Chara- how did you get here?" He shook as she stepped closer and started to sweat.

"I'm asking myself that same question," Chara said, brandishing her knife. Flowey sprang back in fear. She held her knife up to his stem. "Now. I'm going to count to three, and if you don't tell me what's going on, I'll pluck every petal off your face and slice you in half. Okay?"

Cowering in fear, Flowey told Chara about the determination, the LOVE monsters, and about the experiments going on in the lab. He told about Frisk and Toriel and the fight between them. Most importantly, though, he told her about the infection.

"Okay, Asriel," said Chara, " I'm not going to kill you. Yet. Just gather EVERY monster for me and let them melt, and I'll let you live for one extra day. Don't, and I'll cut you so many times you won't even need to turn to dust. Deal?"

"Y-yes, Chara," Flowey said, and he ran away.

Meanwhile, Sans awoke from a deep sleep. He felt his eye burning, his hands aching with pain. He went into the kitchen to grab something to eat. The fridge was almost empty. All that was in there was a bottle of ketchup.

Sans had never drank even a sip of ketchup after the incident with Papyrus. He thought it reminded him too much of determination. Heck, now everywhere he looked, he could see Papyrus standing there... No, he was going crazy. He closed the door to the fridge and trudged over to his workspace. He put on his lab coat and got to work. He moved to the vials of determination and started pouring everything into them to see if something made a reaction. He'd gone so far as pouring liquid nitrogen into the vials. Nothing did a scratch.

"Alphys, maybe we should just give up... Nothing's working." Sans went over to Alphys' bed, where she was searching the Internet for the millionth time to calm herself from the pressure that was on her.

"S-Sans, after all this work, why would we just- g-give up?"

"Because, we're not even DOING anything! We're just repeating ourselves OVER AND OVER TO FIND A CURE TO A FORCE THAT COULD WIPE OUT MONSTERKIND! Can't we just admit defeat?"

Alphys looked down at the floor. Before she could respond, she was grabbed by a giant vine and dug underground. The vine appeared and tried to catch Sans.

Sand acted quick. He teleported behind the vine and threw up his hand. He uprooted the vine and, of course, saw Flowey, but Alphys was gone.

"What... were you doing... trying to grab us like that!?" Sand yelled through clenched teeth.

Flowey ran away.

Sans teleported to the first floor of the lab. He immediately knew who he saw at that moment.

"Looks like the comedian's come to play..."


	7. Kidnap

Meanwhile, while Sans was busy with Chara, Alphys woke up inside of a prison cell in the castle's dungeon. Eyes blurred, she looked around. "W-what.. happened...? Ooh, phew, it was all a dream. M-maybe I should lay off the smoothies tonight, i'm so hung over... too much sugar..." She finally came to her senses. "Oh, i-it wasn't a dream, shi-" she started to say, but she felt a prickly object touch her head. Alphys turned her head slowly. She winced and saw a gurgling mess of vines.

Flowey stood there with an uncomfortable expression. Alphys leapt to grab him, but he immediately dodged and disappeared.

 _I have to get out of here,_ she thought. _Okay, think, Alphys, think, what materials do you have to work with? OH MY GOSH, I CANT THINK, WHAT IS WRONG WITH ME? Okay, calm down, Flowey could kill me any second now, or a determination monster could leak in here,or a rogue monster could break down the doors, and attack, but stay calm, Alphys , stay calm...! You're in huge danger, come on what do I do, what do I do!?_ Alphys' head was spinning. She couldn't think of anything. She started to hyperventilate and sweat. Finally, she fainted and fell flat on her face.

-=====WARNING=====-

This next part may be suitable for younger viewers. Thank you. (contains blood and gore)

-=====WARNING=====-

 _When Alphys woke, she came to her senses and started to try to escape. She sharpened her claws on the wall to break the bars. Little did she know, a monster was behind her that melted into a pool under her feet. The whole room started to melt. She fell into the mess that was the room into a pool of couldn't breathe and tried to rise to the surface. Suddenly, the room started re-materializing into Flowey's face. He laughed at her and melted, blood spurting out of her eyes. Suddenly, she felt herself melting. Everything turned red. And she had a strong urge to find every other monster and infect them. She saw herself melting before her eyes and she laughed maniacally. A giant banana flew in and stabbed Frisk in the heart._ (Author's Note: What, I wanted the dream to be more vivid, okay?) _The banana turned into a melting Papyrus and ripped Undyne's intestines out. Then Papyrus said, "Alphys, want to help?" She walked over to Undyne and started tearing her organs apart-_

-=====End of the horror=====-

YAY

-=====End of the horror=====-

Alphys awoke from her nightmare. Her head hurt like a thousand knives, her whole body steaming hot. She glanced around. She wasn't melting. She was in control. _Thank god, that dream's over..._ She stuck her head through the bars and looked if anyone was around. Suddenly, she heard gurgling. She pulled her lab coat off and hid under it. She heard a cell door open. She realized it was her cell. The melting behemoth hadn't noticed her, though. It sniffed around, smelling magic- and stopped. The cell door closed and Alphys peeked out from under her coat to see a melting Undyne. It noticed her lab coat moving and struck at her with a glowing red spear. Alphys dodged and saw Flowey standing next to stared in horror. Flowey looked at alphys with a blank stare. Then everything went bright red.

Flowey couldn't see Alphys at all through the glowing ball of light. As strange as the glowing ball was, even stranger was Undyne didn't move a muscle. Heck, she didn't seem interested in Alphys anymore. Undyne melted into liquid determination and re-materialized outside of her cell. She burst through the door and Flowey tried to rush toward her, but suddenly, the glowing ball grew and Flowey tried to run but inevitably was caught inside of it. Then the bars to the cell exploded. Alphys appeared, but she wasn't a wimpy dinosaur. She had bloodshot and red eyes. Her wimpy flab became bulging muscle. She held a red lightning bolt. She had two extra glowing red arms. Her claws were sharper than Chara's blade.

"You did this," she said through tears. "YOU DID THIS TO UNDYNE."

Flowey opened his mouth to speak, but couldn't make anything into words.

"I'M GOING TO KILL YOU!"


End file.
